package com.uroad.lib.util.encrypt;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**
 * AES 是一种可逆加密算法，对用户的敏感信息加密处理 对原始数据进行AES加密后，在进行Base64编码转化；
 */
public class AESHelper {
	/*
	 * 加密用的Key 可以用26个字母和数字组成 此处使用AES-128-CBC加密模式，key需要为16位。
	 */
	private String sKey = "88ppadflWxdsjsdF"; // 默认公钥
	private String ivParameter = "android99caiclie";// 默认私钥
	private static AESHelper instance = null;

	private AESHelper() {

	}

	public static AESHelper getInstance() {
		if (instance == null)
			instance = new AESHelper();
		return instance;
	}

	// 加密
	public String encrypt(String sSrc) throws Exception {
		Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
		byte[] raw = sKey.getBytes();
		SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
		IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());// 使用CBC模式，需要一个向量iv，可增加加密算法的强度
		cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
		byte[] decryptString = cipher.doFinal(sSrc.getBytes("utf-8"));
		return new BASE64Encoder().encode(decryptString);// 此处使用BASE64做转码。
	}

	// 解密
	public String decrypt(String decryptString) throws Exception {
		try {
			byte[] raw = sKey.getBytes("ASCII");
			SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());
			cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);

			byte[] encrypted1 = new BASE64Decoder().decodeBuffer(decryptString);// 先用base64解密
			byte[] original = cipher.doFinal(encrypted1);
			String originalString = new String(original, "utf-8");
			return originalString;
		} catch (Exception ex) {
			return null;
		}
	}

	/**
	 * 加密
	 * 
	 * @param skey
	 *            ：公钥
	 * @param ivParameter
	 *            ：私钥
	 **/
	public String encrypt(String sSrc, String sKey, String ivParameter)
			throws Exception {
		Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
		byte[] raw = sKey.getBytes();
		SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
		IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());// 使用CBC模式，需要一个向量iv，可增加加密算法的强度
		cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
		byte[] decryptString = cipher.doFinal(sSrc.getBytes("utf-8"));
		return new BASE64Encoder().encode(decryptString);// 此处使用BASE64做转码。
	}

	/**
	 * 解密
	 * 
	 * @param skey
	 *            ：公钥
	 * @param ivParameter
	 *            ：私钥
	 * **/
	public String decrypt(String decryptString, String sKey, String ivParameter)
			throws Exception {
		try {
			byte[] raw = sKey.getBytes("ASCII");
			SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());
			cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);

			byte[] encrypted1 = new BASE64Decoder().decodeBuffer(decryptString);// 先用base64解密
			byte[] original = cipher.doFinal(encrypted1);
			String originalString = new String(original, "utf-8");
			return originalString;
		} catch (Exception ex) {
			return null;
		}
	}
}
